1. Field of the Invention:
This invention relates to a novel SiC sintered body having an electro-conductive thin layer is a metallized layer and method of producing the same.
2. Prior Art Techniques:
Metallization of a ceramic sintered body is one of the indispensable and important techniques for forming a conductor portion of a ceramic multilayered wiring board. The metallization methods include the methods of forming thin or thick films, electroless plating, and so forth.
As a method of metallizing an alumina ceramic sintered body, an ordinary method comprises coating a metallizing composition containing Mo powder and Mn powder on the surface of the sintered body, sintering the composition to form a metallized layer and thereafter effecting Ni plating, Cu plating and brazing.
Japanese Patent Laid-Open No. 77212/1978 discloses a method of forming a metal film to alumina and beryllia sintered bodies. This method comprises disposing a layer of granular metal powder on the surface of a ceramic substrate, exposing the layer to a binder at a high temperature so as to form an eutectic solution of the metal powder and the binder and directly bonding the metal powder to the substrate as the eutectic solution wets the metal powder and the substrate surface.
A problem of this method is that when applied as such to a non-oxide type ceramic sintered body, the method can not form a metal film having high bonding power to such a ceramic sintered body.
Japanese Patent Laid-Open No. 113683/1980 discloses a metallizing composition for a non-oxide type ceramic sintered body and metallization method. This composition consists of a metal having high wettability to silicon carbide and a metal having low thermal expansion coefficient and a high melting point. The reference also discloses a method which coats this composition in the paste form onto the sintered body and sinters the composition in a non-oxidizing atmosphere. However, this composition is not free from the problem that wettability to solder is low.